In most cases, high-frequency PCBs use special materials. This material property gives them more efficient signal transmission. For this reason, they are very popular on most electronic devices. So, read on to understand High-Frequency PCB material, the power application, and their overall impact on the world of electronics.
What are High-Frequency Circuit Boards?
High-Frequency circuit boards are PCBs used in applications that require the transmission of signals between objects. Usually, the transmission frequency range is between 0.5GHz and 2GHz.
Generally, high-frequency PCBs transfer electromagnetic waves with no additional losses. This makes it better suited for high-speed designs, microwaves, radio frequency, and mobile applications. Additionally, high-frequency materials offer low moisture absorption, faster signal flow, higher chemical resistance, and a more stable dielectric constant.
(illustration of Electromagnetic Waves)
High-Frequency PCB Characteristics
High-frequency PCBs have a small dissipation factor, usually between 0.0019 and 0.025. Due to this, their rate of signal transmission remains constant during transfer. Also, a low dissipation factor value improves signal transmission and helps to reduce signal loss.
Low and Stable Dielectric Constant
The dielectric constant of a material is its ability to store electrical energy in a field. However, high-frequency PCBs have a low and stable dielectric constant, k. As a result, it ensures high-frequency transfer and less signal waiting.
Its ability to resist chemicals is vital in electronic components. And high-frequency PCBs withstand chemicals to a reasonable level. They resist chemical attacks and are less likely to corrode than other components.
Low Moisture Absorption
Most high-frequency PCBs have very low moisture (water) absorption rates. It makes them more resistant to humid environments.
By default, a high-frequency PCB material has very low dimensional stability. So no matter how hot it gets, they stay the same size.
(A high-frequency pcb image)
Common High-Frequency PCB Materials
Some materials are in the table below alongside their dielectric properties. The most common material in High-Frequency Pcb Manufacturing is the PTFE material.
(A PCB with several electronic ICs).
How To Choose A High-Frequency PCB Material
Choosing the correct materials helps get the best out of your setup. High-frequency signals are noise-sensitive, so impedance must be factored into the operating frequency.
Dielectric Constant (Er)
The dielectric constant is a material property that measures the ability to store energy in an electric field. This ability depends on the course of the current and the tolerances in insulation thickness. Also, you need to understand the transmission frequencies of the dielectric materials during testing.
In addition, you need to know the testing method and any other variable existing for the frequency range. Lastly, you also have to consider the stable dielectric conditions and loss material of the PCB that matches the application.
Unlike most PCBs, loss tangent is one of the problems that influence the function of a High-Frequency PCB material. Therefore, the loss of tangent results from a change in the molecular structure of the PCB material. And this change happens when there is a positive move in frequency. Hence, it affects the transmission signals. Also, heat from components closely packed in complex multilayer PCBs affect its frequency signals.
Coefficient of Thermal Expansion(CTE)
The CTE of material refers to the change in the size of the material relative to changes in temperature. In other words, it is a way to determine the thermal reliability of the material. This aspect is, therefore, important during the drilling and assembly stages of High-Frequency PCB fabrication. In addition, having a poor CTE at these stages is bad and, as a result, breaks the PCB material.
Know the Dissipation Factor
The material's dissipation factor (DF) must be low. It is because a high DF critically affects the quality of the transmission signals. So the lower the DF is, the less the signal wastage will be. When the PCB layers send high-speed signals, the DF must be low.
The ground plane is important as well and the understanding of the ground plane as well. Depending on your circuit design, you may or may not divide the ground plane.
(A motherboard PCB design)
Applications of High-Frequency PCB
High-frequency PCB materials are useful in many military ops. Common applications include testing ammunition and firearms to confirm their safety.
Also, high-frequency boards are the base materials of many medical devices.
In general, high-speed PCB materials are essential in industrial vectors. They range from measuring equipment to power indicators.
(An application of high-speed PCB material).
High-frequency PCB materials are the basis of most integrated circuits. Overall, their thermal, electrical, and mechanical properties make them important in a wide range of high-speed design applications.
So, are you looking for quality high-frequency board designs for your next project that needs the transmission of signals? At Ourpcb, we are a certified PCB assembly company based in China. Contact our team today for professional guidance and assistance.